Method and system for PCI express audiovisual output

ABSTRACT

A system and method for using a switch to route graphics data and data for a peripheral data on an interconnect is disclosed. A graphics card includes a switch that is communicatively coupled to a computer system. The switch receives graphics data and data for a peripheral device from the computer system via a first link. The switch routes the data for a peripheral device to a console via a second link and routes the graphics data to a graphics controller via a third link. The graphics controller forms a part of the graphics card and is communicatively coupled to the switch via the third link, wherein the graphics controller generates a video signal to drive a video display.

TECHNICAL FIELD

This disclosure relates in general to the field of computers, and moreparticularly to a system and method for using a switch to routeperipheral and graphics data on an interconnect.

BACKGROUND

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to users is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing users to take advantage of the value of theinformation. Because technology and information handling needs andrequirements vary between different users or applications, informationhandling systems may also vary regarding what information is handled,how the information is handled, how much information is processed,stored, or communicated, and how quickly and efficiently the informationmay be processed, stored, or communicated. The variations in informationhandling systems allow for information handling systems to be general orconfigured for a specific user or specific use such as financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems.

A computer system is one type of information handling system. Examplesof the computer system include a server, a workstation, a desktopcomputer, a notebook computer, a laptop computer, and a hand-helddevice. The computer system, typically, includes a microprocessor,memory, a video display, a keyboard, a mouse, storage devices, mediadrives and optical drives.

The computer system may also include peripheral devices, such as akeyboard, a mouse, disk drives, that connect to the computer viainput/output (I/O) ports. The I/O ports allow the peripheral devices tocommunicate with the processor and in some cases other devices through abus such as a peripheral component interconnect (PCI) bus. In general,the bus may include a parallel or a serial interface for connecting theperipheral devices to the computer system.

FIG. 1 is a schematic view of conventional PCI bus architecture system10 including microprocessor 12 and memory chips 14 connected to chipset20. Microprocessor 12 may connect to chipset 20 via microprocessor bus13. Memory chips 14 communicates to chipset 20 via memory chip bus 15.Chipset 20 includes memory hub 22 and I/O hub 24 connected via chipsetbus 23. Video card 40 receives graphics data from microprocessor 12 andmemory chips 14 through memory hub 22 via video card bus 38. Video card40 creates the video signal for display on a monitor.

I/O hub 24 connects multiple computer components to microprocessor 12and memory chips 14. Typically, the I/O hub 24 connects devices inparallel using a different interface for each type of device. Forexample, I/O hub 24 may include a universal serial bus (“USB”) interfaceto allow USB devices to connect to I/O hub 24 via USB ports 28 e.Similarly, 1394 adapter 30 connects to I/O hub 24 using a PCI interfaceto permit microprocessor 12 and memory chips 14 to communicate with a1394 device. Additionally, encode and decode device (“CODEC”) 32, mainlyused with audio data, connects to I/O hub 24, which provides aconnection for audio components and may also include an interface withinI/O hub 24.

Hard disk drive 26 is one type of storage media that may be used withconventional PCI bus architecture system 10. Hard disk drive 26 connectsto I/O hub 24 via an interface bus dedicated for storage mediainformation, such as a small computer system interface (“SCSI”) and anintegrated device electronics (“IDE”) interface.

PCI cards 34 may connect in parallel to I/O hub 24 via PCI bus 33. PCIcards 34 provide separate connections for allowing a computer componentto communicate with microprocessor 12 and memory chips 14 via PCI cardports 35.

As consumer demand faster computer speeds and performance, technologicalinnovations have exceed the capabilities of current bus architecturessuch as the conventional PCI bus architecture. Technological innovationsincluding high performance graphics, faster memory and microprocessors,networking, and computer devices have created a need for a highperformance, greater bandwidth interconnects. In order to meet thisneed, a new interconnect architecture has been developed to provide highspeed, point-to-point interconnect architecture commonly referred to asPCI Express architecture. The specification for the PCI Expressarchitecture is described in the PCI Express Specification 1.0 availablethrough PCI-SIG, which is hereby incorporated by reference in itsentirety.

PCI Express architecture is a general purpose input/output (I/O) serialinterconnect that provides a highly scalable bandwidth interconnect forattaching devices such as high performance graphics, universal serialbus (USB) ports, networking and other such devices. Because PCI Expressarchitecture may connect to several different types of devices, thearchitecture provides a unifying standard for communications in order toconsolidate these devices on a single interconnect.

System designs for PCI Express architecture, however, provide a separatelink for graphics data and data for peripheral devices. Thus, a computersystem that uses a PCI Express architecture may use a first link forgraphics data and a second link for peripheral data. For example, aprinted circuit board such as a motherboard in a computer system may usea first graphics link to interconnect a processor to a graphicscontroller through a memory hub such that the first graphics linkcarries only graphics data. A second link, formed on the motherboard,typically carries peripheral data from the processor to computercomponents.

SUMMARY

Thus, a need has arisen for a system and method for using a switch toroute graphics data and data for a peripheral device on an interconnect.

A further need has arisen for a system for routing graphics data anddata for a peripheral device on a standard graphics link.

A further need has arisen for a system for routing both a video signaland data to peripheral devices using a single cable.

In accordance with the teachings of the present invention, thedisadvantages and problems associated with routing peripheral data andgraphics data on interconnects have been substantially reduced oreliminated. In some embodiments of the present disclosure, a graphicscard includes a switch that is communicatively coupled to a computersystem. The switch receives graphics data and data for a peripheraldevice from the computer system via a first link. The switch routes thedata for a peripheral device to a console via a second link and routesthe graphics data to a graphics controller via a third link usingstandard PCI Express mechanisms. The graphics controller forms a part ofthe graphics card and is communicatively coupled to the switch via thethird link, wherein the graphics controller generates a video signal todrive a video display.

In other embodiments, a system for routing graphics data and data for aperipheral device in a computer system includes a processor, a memory, amemory hub, a first link, and a graphics card. The memory iscommunicatively coupled to the processor via the memory bridge. Thefirst link communicatively connects the graphics card to the memory andthe processor via the memory bridge, wherein the first link carriesgraphics data and data for a peripheral device. The graphics cardcouples to the computer system and includes a first switch and agraphics controller. The first switch is disposed on the graphics cardand is communicatively coupled to the computer system. The first switchreceives the graphics data and the data for the peripheral device fromthe computer system via the first link. The first switch routes the datafor the peripheral device onto a second link and routes the graphicsdata onto a third link. The graphics controller forms a part of thegraphics card and is communicatively coupled to the first switch via thethird link. The graphics controller receives the graphics data andgenerates a video signal to drive a video display.

In further embodiments, a method for using a switch to route graphicsdata and data for a peripheral device on an interconnect includesreceiving data at a switch coupled to a graphics card via a first link.The switch determines whether the data is graphics data or data for aperipheral device based on an address contained in the data. Followingthe determination, the switch routes the graphics data to a second linkand the data for the peripheral device to a third link.

The present disclosure contains a number of important technicaladvantages. One technical advantage is providing a switch for routinggraphics data or data for a peripheral device on a high bandwidthinterconnect. The high bandwidth interconnect incorporates the PCIExpress architecture to transmit data in packet-based split transactionsor packets along the interconnect. Because the switch discriminatesbetween graphics data and data for a peripheral device, the switchroutes the graphics data to a graphics controller via a graphics link.Data for a peripheral device, however, are forwarded to the peripheraldevice or other endpoint connection via a second link.

Another technical advantage includes a system and method for routinggraphics data and data for a peripheral device on a standard graphicslink. Because the PCI Express architecture uses a standardized transferformat that includes address information, both graphics data and datafor a peripheral device may be sent along a standard graphics link. Aswitch placed on the graphics card routes the data to the appropriatedevice based on the address information. Thus, a standard graphics linkmay be used to receive and send both graphics data and data forperipheral device.

A further technical advantage includes a system for routing both a videosignal and data for a peripheral device using a single cable. Because avideo signal, generated by the graphics card, and data for a peripheraldevice are routed from a switch on the graphics card, a singleconnection that includes both the video signal and data for theperipheral device may be provided on the graphics card. Thus, a singlecable connection may allow a user to place peripheral devices and amonitor within reach of the user, while the computer system is placed ata distance.

All, some, or none of these technical advantages may be present invarious embodiments of the present invention. Other technical advantageswill be apparent to one skilled in the art from the following figures,descriptions, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the embodiments of the presentdisclosure and advantages thereof may be acquired by referring to thefollowing description taken in conjunction with the accompanyingdrawings, in which like reference numbers indicate like features, andwherein:

FIG. 1 is a schematic view of a conventional PCI bus architecturesystem;

FIG. 2 is a schematic view of a PCI Express architecture system;

FIG. 3 is a schematic view of a computer system and console using aswitch to route graphics data and data for a peripheral device on aninterconnect according to an example embodiment of the presentdisclosure;

FIG. 4 is a schematic view of a graphics card including a switch toroute graphics data and data for a peripheral device on an interconnectaccording to an example embodiment of the present disclosure; and

FIG. 5 illustrates a flowchart for using a switch to route graphics dataand data for a peripheral device on an interconnect.

DETAILED DESCRIPTION

Preferred embodiments of the present disclosure and their advantages arebest understood by reference to FIGS. 1 through 5, where like numbersare used to indicate like and corresponding parts.

For purposes of this disclosure, an information handling system mayinclude any instrumentality or aggregate of instrumentalities operableto compute, classify, process, transmit, receive, retrieve, originate,switch, store, display, manifest, detect, record, reproduce, handle, orutilize any form of information, intelligence, or data for business,scientific, control, or other purposes. For example, an informationhandling system may be a personal computer, a network storage device, orany other suitable device and may vary in size, shape, performance,functionality, and price. The information handling system may includerandom access memory (RAM), one or more processing resources such as acentral processing unit (CPU) or hardware or software control logic,ROM, and/or other types of nonvolatile memory. Additional components ofthe information handling system may include one or more disk drives, oneor more network ports for communicating with external devices, as wellas various input and output (I/O) devices, such as a keyboard, a mouse,and a video display. The information handling system may also includeone or more buses operable to transmit communications between thevarious hardware components.

Referring to FIG. 2, PCI Express architecture system 110 may includecentral processing unit (“CPU”) 112, memory 114, host bridge 120 and I/Obridge 122. CPU 112 communicates with host bridge 120 via CPU bus 113.Memory 114 communicates with host bridge 120 via memory bus 115.

PCI Express architecture uses a protocol that includes a serial,point-to-point, switched architecture for the transmission of data on aninterconnect. Accordingly, the data is partitioned into packet-basedsplit transactions or packets, which contain an address for routing eachpacket to the correct destination on the interconnect. The interconnecthaving the PCI Express architecture includes two or more differentialsignal pairs in which one pair is used for transmitting information andthe other pair for receiving information on the interconnect. Byincreasing the quantity of differential signal pairs, the interconnectincreases the bandwidth by creating multiple signal lanes fortransmitting information.

Graphics controller 136 connects to host bridge 120 via PCI Express link130, which uses the PCI Express architecture. Graphics controller 136communicates with CPU 112 and memory 114 through host bridge 120 togenerate a video signal. Graphics controller 136 may transmit the videosignal to a display or monitor connected at graphics controller port135.

Additionally, I/O bridge 122 may communicate through I/O link 123 andhost bridge 120 to provide communications for hard disk drive 26. Harddisk drive 26 may communicate with CPU 112 and memory 114 through I/Obridge 122 via host bridge 120. Similarly, optical drives such as CD-ROMand DVD drives may connect to I/O bridge 122 to access other componentsof PCI Express architecture system 110.

PCI bridge 137 connects to host bridge 120 at the I/O bridge 122 via PCIExpress link 130. PCI bridge 137 provides a connection slot for one ormore PCI ports 138 to access other components of PCI Expressarchitecture system 110. A PCI card may attach to each PCI port 138 inthe system.

Switch 125 connects to I/O bridge 122 via PCI Express link 130. Switch125 allows multiple endpoint connections 140 to share a singleinterconnect by directing the packets of information to thecorresponding endpoint connection 140 as defined by the address in thepacket. Endpoint connections 140 may connect to switch 125 via PCIExpress links 130. Examples of endpoint connection 140 include hostcontrollers such as a 1394 host controller or a PCI Express adaptercards. Other endpoint connections 140 can be connected through a switch125, which connects via PCI Express link 130 using PCI Express linkcable 131 that includes the PCI Express link.

FIG. 3 is a schematic view of computer system 200 and console 202 usingswitch 125 to route graphics data and data for a peripheral device on aninterconnect such as PCI Express link 130. Typically, computer system200 includes CPU 112, memory 114, I/O hub device 226, hard disk drives26, and memory bridge 210. CPU 112 and memory 114 connect through memorybridge 210 to provide graphics data and data for peripheral devices. CPU112 may include processors, microprocessors, and any other suitableprocessing resource. Memory 114 may include volatile storage such asrandom access memory (RAM) and non-volatile memory such as read onlymemory (ROM).

I/O hub device 226 by be coupled to memory bridge 210 via a computersystem link that allows hard disk drive (HDD) 26 and other devices tocommunicate with computer system 200. Other computer devices may connectto components of computer system 200 via endpoint connections 140.Typically, the computer devices placed in computer system 200 includethose devices that have infrequent physical interaction with a user. Forexample, a CD-ROM drive requires physical interaction with a user toremove and insert a CD from the drive. However, hard disk drive 26 ismerely access through computer system 200 via input devices and does notrequire physical interaction with a user.

Graphics card 220 may form a part of computer system 200 and may includeswitch 125 and graphics controller 136. Switch 125 connects to memorybridge 210 via memory bridge link 212, which may use a PCI Expressarchitecture. Switch 125 receives data for a peripheral device andgraphics data from memory bridge 210. Switch 125 routes the data to theappropriate location based on the address contained in each data packetsuch that the graphics data is sent to graphics controller 136 viagraphics controller link 130 a. In some instances, graphics controllerlink 130 a is PCI Express.

Graphics controller 136 uses the graphics data to produce a videosignal. The video signal may be transmitted from graphics controller 136through video bus 230. Typically, video bus 230 carries the videosignals from computer system 200 to console 202 via video cable 231.Video signals may include analog signals and/or digital signalsdepending upon the type of monitor 235 connected to console 202. Forexample, a digital video interface (DVI), created by the Digital DisplayWorking Group (DDWG), may be used to generate a video signal to drive adigital flat-panel display, using a VESA Digital Flat Panel Standard(DFP), associated with console 202. Other examples of video signalsinclude DVI-A that is used to provide an analog signal, video graphicsarray (VGA), and any other video signal suitable to drive a display.

Additionally, switch 125 may route the data for the peripheral device toperipheral link 130 b in order to access the peripheral devices or othercomputer components. Peripheral link 130 b includes a PCI Express link.The other computer components may include endpoint connections 140,other switches 125, and I/O hub device 226. Endpoint connections 140 maysupport attachment of a mouse, a keyboard, a speaker, a microphone, anoptical drive (e.g., CD-ROM and DVD drives), a magnetic drive (e.g., afloppy disk drive), a camera, and any other suitable component tocomputer system 200 through other intermediate interfaces such as AC 97and USB.

Console 202 may include I/O hub device 226 for connecting a plurality ofperipheral devices to computer system 200. In one example embodiment,I/O hub device 226 includes switch 125 that receives data fromperipheral link 130 b via peripheral cable link 151, which typicallyuses the PCI Express architecture. Switch 125 coupled to I/O hub device226 may be used to interface and route data to and from differentperipheral devices.

In one example embodiment, I/O hub device 226 interfaces data for aperipheral device such as audio data to CODEC device 240, which mayfurther connect with other audio components such as headset 260. I/O hubdevice 226 may also interface data for optical drives such as CD ROMdevice 242 and DVD device 248. Further, I/O hub device 226 may interfacedata for 1394 adapter 244, which may provide 1394 port 246 to allowother devices such as 1394 devices 247 to access computer system 200 viaconsole 202. In addition, I/O hub device 226 may interface with one ormore USB ports 251 to connect other devices such as USB device 254 andUSB Mouse/Keyboard 250 to computer system 200.

In some example embodiments, peripheral cable link 151 and video cable231 may be formed at a single connector. The single connector allows forboth video signals and data for peripheral devices to be sent to aconsole in a single cable. Although both video signals and data forperipheral devices may be included in a common cable, the cable may beshielded between the two different interconnects, namely oneinterconnect being a bus for video signals and the other interconnectbeing a link incorporating the PCI Express architecture.

Computer system 200 may be designed to operate with or without console202. As such, all components described in console 202 may be included incomputer system 200. Thus, depending on the design of the system, all,some or none of components associated with console 202 may be includedin computer system 200, whether or not computer system 200 attaches toconsole 202. In some instances, computer system 200 includes thesecomponents and attaches to console 202; however, the system is designedto use the components associated with console 202. In addition, becausePCI Express will discover all devices connected to the link, computersystem 200 or console 202 may use a conventional display without havingany peripherals associated with the display.

FIG. 4 is a schematic view of graphics card 220 including switch 125 toroute graphics data and data for peripheral devices on an interconnect.Graphics card 220 may receive graphics data and data for peripheraldevices at switch 125 via PCI Express link 130. Typically, switch 125 isformed as a part of graphics card 220 and provides communications tocomputer system 200 via PCI Express link 130.

Because the PCI Express architecture uses a packet-based splittransaction protocol, each packet of data may be sent in a separatetransaction on PCI Express link 130. For example, a first packet of datafrom computer system 200 may include data for a peripheral device thatis routed via switch 125 to the appropriate peripheral device. Before aresponse is sent from the peripheral device, a second packet of data maybe received at switch 125 that may include graphics data that is routedto graphics controller 136 via graphics link 130 a, wherein graphicscontroller 136 couples to video memory 272 to produce a video signal.The peripheral device may send a response to the first data packet backalong peripheral link 130 b to computer system 200 via switch 125.

In one example embodiment, graphics card 220 includes graphics cardconnector 236 that may be used to receive both peripheral link 130 b andvideo bus 230. Graphics card connector 236 may be formed to allow asingle connector to send both the video signals and the data for theperipheral device to console 202 or another similar device. Accordingly,graphics card connector 236 may allow for a single cable to be usedbetween computer system 220 and console 202.

FIG. 5 illustrates a flowchart for using switch 125 to route graphicsdata and data for a peripheral device on an interconnect. At step 290,data is received at switch 125. The data may include graphics data ordata for a peripheral device. The data is sent along an interconnectthat incorporates the PCI Express architecture protocol, whichpartitions the data into packet-based transactions or packets. Eachpacket may include an address for routing the data to the correctdevice.

At step 292, switch 125 determines whether the data is graphics databased on the address contained in the packet. In the following exampleembodiment, switch 125 discriminates between data for a peripheraldevice and graphics data. In other embodiments, switch 125 maydiscriminate among several different types of data. If switch 125determines that the data is graphics data, signal 125 routes the data tographics controller 136 via graphics link 130 a, at step 294.

However, if switch 125 determines that the data is data for a peripheraldevice, switch 125 routes the data to peripheral link 130 b. In someembodiments, data for the peripheral device may be routed to an endpointdevice through other switch 125, I/O hub device 226, or other interfacesbefore reaching the appropriate peripheral device.

Although the present disclosure has been described with respect to aspecific embodiment, various changes and modifications will be readilyapparent to one skilled in the art. The present disclosure is notlimited to the illustrated embodiment, but encompasses such changes andmodifications that fall within the scope of the appended claims.

1. A graphics card, comprising: a switch associated with the graphicscard and communicatively coupled to a computer system, the switchoperable to receive graphics data and data for a peripheral device fromthe computer system via a first link; the switch operable to route thedata for a peripheral device to a console via a second link and to routethe graphics data to a graphics controller via a third link; and thegraphics controller forming a part of the graphics card andcommunicatively coupled to the switch via the third link, the graphicscontroller operable to generate a video signal to drive a video display.2. The graphics card of claim 1 further comprising the switch forming apart of the graphics controller.
 3. The graphics card of claim 1 whereinthe video signal comprises a digital signal.
 4. The graphics card ofclaim 1 wherein the video signal comprises an analog signal.
 5. Thegraphics card of claim 1 further comprising a video memory disposed onthe graphics card, the video memory communicatively coupled to agraphics controller to generate a video signal.
 6. The graphics card ofclaim 1 wherein the first link, the second link, and the third linkcomprise high bandwidth links of a single interconnect.
 7. A system forrouting graphics data and data for a peripheral device in a computersystem, the system comprising: a processor; a memory; a first linkcommunicatively connected between the memory and the processor, thefirst link operable to carry the graphics data and the data for theperipheral device; and a graphics card coupled to the computer system,the graphics card comprising: a first switch disposed on the graphicscard and communicatively coupled to the computer system, the firstswitch operable to receive the graphics data and the data for theperipheral device from the computer system via the first link; the firstswitch operable to route the data for the peripheral device to a secondlink and to route the graphics data to a third link; and the graphicscontroller forming a part of the graphics card and communicativelycoupled to the first switch via the third link, the graphics controlleroperable to receive the graphics data and generate a video signal todrive a video display.
 8. The system of claim 7 further comprising anI/O hub device communicatively coupled to the first switch via thesecond link, wherein the I/O hub device receives the data for theperipheral device.
 9. The system of claim 8 further comprising a secondswitch forming a part of the I/O hub device in a console, the secondswitch operable to route the data for the peripheral device attachedthrough an endpoint connection in the console via the I/O hub device.10. The system of claim 9 wherein the data for the peripheral deviceattached at the endpoint connection through other intermediateinterfaces comprises data for a computer device, wherein the computerdevice is selected from a group consisting of a mouse, a keyboard, aspeaker, a microphone, an optical drive, a magnetic drive, a camera,another switch, and a second input/output hub device.
 11. The system ofclaim 7 further comprising an I/O hub device associated with thecomputer system, the I/O hub device including an endpoint connection,wherein the I/O hub device operable to receive data from the computersystem via a computer system link.
 12. The system of claim 11 furthercomprising a hard disk drive coupled to the I/O hub device, wherein theI/O hub device is disposed in the computer system.
 13. The system ofclaim 7 wherein the first link comprises high bandwidth interconnect.14. A method of using a switch to route graphics data and data for aperipheral device on an interconnect, the method comprising: receivingdata at a switch coupled to a graphics card via a first link;determining whether the data is the data for the peripheral device orthe graphics data based on an address contained in the data; and basedon the determination, routing the graphics data to a second link and thedata for the peripheral device to a third link.
 15. The method of claim14 wherein the first link comprises a high bandwidth link of aninterconnect architecture.
 16. The method of claim 14 furthercomprising: transmitting the graphics data to a graphics controller viathe second link; and generating a video signal operable to drive a videomonitor based on the graphics data received at the graphics controller,wherein the video signal is sent to the video monitor via a video bus.17. The method of claim 16 wherein the video signal comprises a digitalsignal.
 18. The method of claim 16 wherein the video signal comprises ananalog signal.
 19. The method of claim 14 further comprisingtransmitting the data for the peripheral device via the third link. 20.The method of claim 14 wherein the data comprises a packet-basedtransaction.